**1. Serena deposited $ 50000 in a bank which charged an interest of 5 percent p.a. Calculate the interest and the amount she earned after 2 years.**

a) $5000, $50000

b) $5000, $55000

c) $10000, $50000

d) $10000, $55000

**Answer:** b) $5000, $55000

**Explanation:** Given: Principal (P) = $50000

Time (T) = 2 years,

Rate (R) = 5% p.a.

Substitute the values in the simple interest formula;

S.I. = (P × R × T)/100

= (50000 x 5 x 2)/100

= $5000

She earned interest of $5000.

Amount (A) = Principal (P) + Interest (I)

50000 + 5000 = 55000

Serena got $55000.

**2. Find simple interest on $2000 at 5% per annum for 3 years.**

a) $300

b) $200

c) $100

d) $50

**Answer:** a) $300

**Explanation:** Principal = $2000

Rate = 5% p.a.

T = 3 years

S.I. = (P × R × T)/100

= (2000 × 5 × 3)/100

= $300

**3. Alfred took a loan of $20000 from a bank on 4 February 2009 at the rate of 8% p.a. and paid back the same on 6th July 2009. Find the total amount paid by Alfred.**

a) $22879.23

b) $21908.20

c) $21098.18

d) $20666.30

**Answer:** d) $20666.30

**Explanation:** P = $20000

R = 8% p.a.

T = 152/365

Time = February + March + April + May + Jun + July

= 24 days + 31 days + 30 days + 31 days + 30 days + 6 days

= 152 days

Therefore, S.I. = (P × R × T)/100

= (20000 × 8 × 152)/(100 × 365)

= $(40 × 8 × 152)/73

= $666.30

Therefore, the amount paid = $(20,000 + 666.30) = $20666.30

**4. What is the interest rate on a $2,000 loan that earns $200 in simple interest over 2 years?**

a) 5%

b) 10%

c) 15%

d) 20%

**Answer:** a) 5%

**Explanation:** Simple Interest = P x R x T

$200 = $2,000 x Interest Rate x 2

Interest Rate = $200 / ($2,000 x 2)

= 0.05 or 5%

**5. A person borrows $3000 from a bank at a 7% annual interest rate. How much interest will he has to pay in 2 years?**

a) $420

b) $340

c) $210

d) $100

**Answer:** a) $420

**Explanation:** Given P = $3000

R = 7% (or 0.07)

T = 2 years

Interest = P x R x T

Interest = $3000 x 0.07 x 2

= $420

**1. At what percent will $1500 amount to $2400 in 4 years?**

a) 12%

b) 13%

c) 14%

d) 15%

**Answer:** d) 15%

**2. What is the simple interest earned on a $1,000 loan at a 5% interest rate for 2 years?**

a) $50

b) $100

c) $150

d) $200

**Answer:** b) $100

**3. What is the simple interest to be paid on a $5,000 loan at a 10% interest rate for 3 years?**

a) $1000

b) $1200

c) $1500

d) $2500

**Answer:** c) $1500

**4. Stanley borrowed $8,000 from a bank at a 15% interest rate for 4 years. How much money he has to pay in total?**

a) $12800

b) $10000

c) $8000

d) $4800

**Answer:** a) $12800

**5. What is the simple interest earned on a $5,500 loan at a 7% interest rate for 1.5 years?**

a) $577.5

b) $432.3

c) $389.2

d) $200.1

**Answer:** a) $577.5

**6. A person deposited $2000 in a bank account and earns a 5% annual interest rate. How much interest will he earn in one year?**

a) $400

b) $300

c) $200

d) $100

**Answer:** d) $100

**7. A person invests $5000 in a stock that earns a 12% annual interest rate. How much interest will he earn in 3 years?**

a) $1000

b) $1200

c) $1400

d) $1800

**Answer:** d) $1800

**8. A person takes out a loan of $10000 at a 15% annual interest rate. How much interest he has to pay in 4 years?**

a) $3000

b) $4000

c) $6000

d) $8000

**Answer:** c) $6000

**9. If you invest $5000 at a 6% interest rate for 3 years, how much money will you have at the end of the 3 years?**

a) $5000

b) $5200

c) $5400

d) $5900

**Answer:** d) $5900

**10. In how much time will a sum of money triple itself at 15 % p.a.?**

a) 12.5 years

b) 13.3 years

c) 15.2 years

d) 16 years

**Answer:** b) 13.3 years

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